Solar cell and photovoltaic module

Abstract

The invention discloses a solar cell and a photovoltaic module, the solar cell comprises a cell body, the surface of the cell body is provided with a plurality of electrodes, the surface has a first direction and a second direction which are intersected, and the plurality of electrodes are arranged at intervals along the first direction; a characteristic structure is arranged on the edge of one side, close to the second direction, of the battery body and is used for identifying and positioning; wherein the feature structure in the second direction corresponds to at least one electrode, and the orthographic projection of the feature structure in the first direction is overlapped with the orthographic projection of at least part of the electrodes. The feature structure is arranged at the position, close to the edge, of the battery body, so that recognition and positioning in the battery processing process are facilitated, the position relation between the feature structure on the battery body and the electrode is limited, design and processing of the feature structure on the battery body are facilitated, meanwhile, the dead zone area in the battery body can be reduced, and the battery quality is improved. Therefore, the power generation area of the cell body is increased, and the conversion efficiency of the solar cell is improved.

Description

Technical Field

[0001] This application belongs to the field of photovoltaic technology, and particularly relates to a solar cell and a photovoltaic module. Background Art

[0002] A solar cell is a device that directly converts light energy into electrical energy. With the continuous development of photovoltaic technology, back-contact solar cells have been widely used and attracted attention because their electrodes are arranged on the back of the cell, and there are no grid lines on the front, which can avoid the occlusion of the grid lines on the front of the cell, enabling the entire front area of the cell to be used for absorbing sunlight, improving the light absorption rate of the cell, and thus increasing the conversion efficiency of the cell.

[0003] In the manufacturing process of back-contact cells, since both the positive and negative grid lines are arranged on the back, during the patterning process, it is necessary to identify the Mark points in the previous stage for alignment in the subsequent stage, and usually, Mark points need to be set on the back of the cell for identification and positioning. However, in the cells of related technologies, the setting of Mark points does not consider the impact on the back space of the cell, resulting in a large dead area on the back of the cell and reducing the conversion efficiency of the cell. Summary of the Invention

[0004] This application aims to provide a solar cell and a photovoltaic module, which can solve the problem that in the cells of related technologies, when setting Mark points, the impact on the back space of the cell is not considered, resulting in a large dead area on the back of the cell.

[0005] To solve the above technical problems, this application is implemented as follows:

[0006] In a first aspect, an embodiment of this application provides a solar cell, including: a cell body, on the surface of the cell body are provided a plurality of electrodes, the surface has an intersecting first direction and second direction, and the plurality of electrodes are arranged at intervals along the first direction; a feature structure is provided on one side edge of the cell body close to the second direction, and the feature structure is used for identification and positioning; wherein, along the second direction, the feature structure corresponds to at least one of the electrodes, and along the first direction, the orthographic projection of the feature structure overlaps with the orthographic projection of at least a part of the electrodes.

[0007] Optionally, along the second direction, the distance from the feature structure to the adjacent edge of the cell body is H1, satisfying: H1 ≤ 2000 μm.

[0008] Optionally, along the second direction, the distance from the feature structure to the corresponding electrode is H2, satisfying: H2 ≤ 3000 μm.

[0009] Optionally, a first power generation region and a second power generation region with opposite conductive types are provided on the surface of the battery body. The first power generation region and the second power generation region are alternately arranged at intervals along the first direction, and the electrodes are provided in both the first power generation region and the second power generation region; the width of the second power generation region along the first direction is greater than the width of the first power generation region along the first direction, and the feature structure corresponds to at least one of the second power generation regions in the second direction.

[0010] Optionally, when the feature structure corresponds to one of the second power generation regions, the width of the feature structure along the first direction is less than or equal to the width of the second power generation region along the first direction.

[0011] Optionally, when the feature structure corresponds to one of the second power generation regions, the electrode in the second power generation region corresponding to the feature structure is a preset electrode, the preset electrode has a center line extending along the second direction, and the midpoint of the feature structure is located on the extension line of the center line.

[0012] Optionally, a semiconductor film layer is further provided on the surface of the battery body, and the electrode is provided on the side of the semiconductor film layer away from the battery body; when the feature structure corresponds to one of the second power generation regions, the doping type of the semiconductor film layer on the second power generation region is the same as the doping type of the semiconductor film layer on the feature structure.

[0013] Optionally, when the feature structure corresponds to one of the second power generation regions and one of the first power generation regions, the width of the feature structure along the first direction is D0, the width of the second power generation region along the first direction is D1, the width of the first power generation region along the first direction is D2, and the distance between adjacent first power generation regions and second power generation regions is D3, satisfying: D0≤D1+D2+D3.

[0014] Optionally, the electrode corresponding to the feature structure along the second direction is a first target electrode, and the electrodes other than the first target electrode among the multiple electrodes are second target electrodes. The length of the first target electrode along the second direction is less than the length of the second target electrode along the second direction.

[0015] Optionally, the second target electrode includes a first sub-electrode and a second sub-electrode other than the first sub-electrode; the edge of the battery body corresponding to the feature structure is a first edge. Along the second direction, the distance between the first sub-electrode and the first edge is greater than the distance between the second sub-electrode and the first edge, and the first sub-electrode is close to the feature structure.

[0016] Optionally, an edge of the battery body corresponding to the feature structure is a first edge, and along the second direction, a distance between the feature structure and the first edge is less than or equal to a distance between the second target electrode and the first edge.

[0017] Optionally, a positive projection of the feature structure on the surface is in a shape of one or a combination of two or more of a circle, an ellipse, a polygon, a cross, and an annulus.

[0018] In a second aspect, an embodiment of the present application provides a photovoltaic module, including a plurality of battery strings, where each battery string includes a plurality of solar cells and a plurality of interconnects for connecting the plurality of solar cells in series; wherein, the solar cell is the solar cell described in the first aspect.

[0019] In the present application, by providing a feature structure at a position close to an edge on the battery body, it is convenient for identification and positioning during the battery processing; meanwhile, by setting a position of the feature structure on the battery body, the feature structure corresponds to at least one electrode along the second direction, and a positive projection of the feature structure along the first direction overlaps with a positive projection of at least a part of the electrodes. In this way, by defining a positional relationship between the feature structure and the electrodes on the battery body, it is not only convenient for the design and processing of the feature structure on the battery body, but also can reduce a dead zone area in the battery body, thereby increasing an area available for power generation of the battery body and improving a conversion efficiency of the solar cell.

[0020] Additional aspects and advantages of the present application will be given in part in the following description, become apparent in part from the following description, or be learned through practice of the present application. BRIEF DESCRIPTION OF THE DRAWINGS

[0021] The above and / or additional aspects and advantages of the present application will become apparent and be readily understood from the description of the embodiments in conjunction with the following drawings, where:

[0022] Figure 1 is a first schematic structural diagram of a solar cell according to an embodiment of the present application;

[0023] Figure 2 is a second schematic structural diagram of a solar cell according to an embodiment of the present application;

[0024] Figure 3 is a third schematic structural diagram of a solar cell according to an embodiment of the present application;

[0025] Figure 4 is a fourth schematic structural diagram of a solar cell according to an embodiment of the present application;

[0026] Figure 5 is a fifth schematic structural diagram of a solar cell according to an embodiment of the present application;

[0027] Figure 6 is the sixth structural schematic diagram of the solar cell according to an embodiment of the present application;

[0028] Figure 7 is the seventh structural schematic diagram of the solar cell according to an embodiment of the present application;

[0029] Figure 8 is one of the schematic diagrams of the preparation process of the solar cell according to an embodiment of the present application;

[0030] Figure 9 is another schematic diagram of the preparation process of the solar cell according to an embodiment of the present application;

[0031] Figure 10 is the third schematic diagram of the preparation process of the solar cell according to an embodiment of the present application;

[0032] Figure 11 is the fourth schematic diagram of the preparation process of the solar cell according to an embodiment of the present application;

[0033] Figure 12 is the fifth schematic diagram of the preparation process of the solar cell according to an embodiment of the present application;

[0034] Figure 13 is the sixth schematic diagram of the preparation process of the solar cell according to an embodiment of the present application;

[0035] Figure 14 is the seventh schematic diagram of the preparation process of the solar cell according to an embodiment of the present application;

[0036] Figure 15 is the eighth schematic diagram of the preparation process of the solar cell according to an embodiment of the present application;

[0037] Figure 16 is the schematic diagram of the setting position of the characteristic structure according to an embodiment of the present application.

[0038] Reference numerals:

[0039] 10: Battery body; 11: First power generation area; 12: Second power generation area; 10a: First edge; 20: Electrode; 21: First target electrode; 22: Second target electrode; 221: First sub-electrode; 222: Second sub-electrode; 30: Characteristic structure; X: First direction; Y: Second direction; 100: Silicon substrate; F: Front; B: Back; 200: First passivation layer; 300: First conductive layer; 400: Mask layer; 500: Second passivation layer; 600: Second conductive layer; 700: Third passivation layer; 800: Anti-reflection layer; 900: Transparent conductive layer. Detailed implementation manners

[0040] Embodiments of the present application will be described in detail below. Examples of the embodiments are shown in the accompanying drawings, where like or similar reference numerals denote like or similar elements or elements having like or similar functions throughout. The embodiments described below by referring to the drawings are exemplary only for explaining the present application and should not be construed as limiting the present application. All other embodiments obtained by those of ordinary skill in the art based on the embodiments in the present application without creative efforts belong to the scope of protection of the present application.

[0041] The terms "first" and "second" in the description and claims of the present application may explicitly or implicitly include one or more of such features. In the description of the present application, unless otherwise specified, the meaning of "a plurality" is two or more. In addition, "and / or" in the description and claims means at least one of the connected objects, and the character " / " generally means an "or" relationship between the associated objects before and after.

[0042] In the description of the present application, it should be understood that the orientation or positional relationship indicated by the terms "center", "longitudinal", "transverse", "length", "width", "thickness", "upper", "lower", "front", "rear", "left", "right", "vertical", "horizontal", "top", "bottom", "inner", "outer", "clockwise", "counterclockwise", "axial", "radial", "circumferential", etc. is based on the orientation or positional relationship shown in the accompanying drawings, and is only for the convenience of describing the present application and simplifying the description, rather than indicating or implying that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and thus should not be construed as limiting the present application.

[0043] In the description of the present application, it should be noted that, unless otherwise clearly specified and defined, the terms "mounted", "connected" and "coupled" should be understood in a broad sense. For example, it may be a fixed connection, a detachable connection, or an integral connection; it may be a mechanical connection or an electrical connection; it may be directly connected or indirectly connected through an intermediate medium, and it may be the communication inside two elements. For those of ordinary skill in the art, the specific meanings of the above terms in the present application can be understood according to specific circumstances.

[0044] The solar cell and photovoltaic module provided by the embodiments of the present application will be described in detail below with reference to the accompanying drawings through specific embodiments and their application scenarios.

[0045] Such as Figure 1 and Figure 2As shown, a solar cell according to some embodiments of the present application includes: a cell body 10, on the surface of the cell body 10, a plurality of electrodes 20 are provided, the surface has an intersecting first direction X and second direction Y, and the plurality of electrodes 20 are arranged at intervals along the first direction X; a feature structure 30 is provided at one side edge of the cell body 10 close to the second direction Y, and the feature structure 30 is used for identification and positioning; wherein, along the second direction Y, the feature structure 30 corresponds to at least one electrode 20, and along the first direction X, the orthographic projection of the feature structure 30 overlaps with the orthographic projection of at least part of the electrodes 20.

[0046] In the embodiments of the present application, by providing the feature structure 30 at a position close to the edge on the cell body 10, it is convenient for identification and positioning during the battery processing; at the same time, by setting the position of the feature structure 30 on the cell body 10, the feature structure 30 corresponds to at least one electrode 20 along the second direction Y, and the orthographic projection of the feature structure 30 along the first direction X overlaps with the orthographic projection of at least part of the electrodes 20. In this way, by defining the positional relationship between the feature structure 30 and the electrodes 20 on the cell body 10, it is not only convenient for the design and processing of the feature structure 30 on the cell body 10, but also can reduce the dead zone area in the cell body, thereby increasing the area of the cell body available for power generation and improving the conversion efficiency of the solar cell.

[0047] It can be understood that in the process of the solar cell technology, it is necessary to prepare the electrodes 20 on the surface of the cell body 10. Since a high positioning accuracy is required in the process of preparing the electrodes 20, in order to improve the positioning accuracy, a feature structure 30 (i.e., a mark point) is provided on the cell body 10 for identification and positioning during the battery preparation process.

[0048] Of course, the feature structure 30 provided on the cell body 10 can not only be applied to the preparation process of the electrodes 20, but also can be applied to other processes in the solar cell manufacturing process, and can also be applied to the process of preparing a photovoltaic module from the solar cell. Those skilled in the art can flexibly apply it according to actual needs and are not limited herein.

[0049] In some embodiments, the feature structure 30 can be a convex or concave structure formed on the surface of the cell body 10, which is convenient for being recognized by the recognition device. Among them, as Figures 1 to 5 shown, the orthographic projection contour shape of the feature structure 30 on the surface of the cell body 10 includes but is not limited to: one or a combination of two or more of a circle, an ellipse, a polygon, a cross, and a ring. Of course, the specific structure of the feature structure 30 provided on the cell body 10 can be flexibly set according to actual needs, and the embodiments of the present application do not limit this.

[0050] Specifically, a plurality of electrodes 20 arranged at intervals along the first direction X are provided on the surface of the battery body 10, and each electrode 20 extends along the second direction Y. Furthermore, a feature structure 30 is provided at a position close to the edge on the surface of the battery body 10, so that the feature structure 30 corresponds to at least one electrode 20 along the second direction Y, and the orthographic projection of the feature structure 30 along the first direction X overlaps with the orthographic projection of at least part of the electrodes 20. Wherein, the surface includes the light-receiving surface and / or the backlight surface of the battery body 10, and the "corresponding" means that the orthographic projection of the feature structure 30 along the second direction Y overlaps with the orthographic projection of at least one electrode 20.

[0051] As Figure 1 and Figure 2 shown, a plurality of electrodes 20 are provided on the surface of the battery body 10, and each electrode 20 extends along the second direction Y. By shortening the length of part of the electrodes 20 along the second direction Y, an electrode blank area is formed at the edge position of the battery body 10, and then the feature structure 30 is arranged in the electrode blank area. It can be understood that since there is no electrode 20 arranged in the area where the feature structure 30 is arranged, the carriers generated by the conversion of the battery body 10 cannot be effectively collected, thus forming a dead zone. In this application, by restricting the setting position of the feature structure 30 within a certain area, it is not only convenient for identification and positioning, but also the electrodes 20 on both sides of the feature structure 30 along the first direction X can be unaffected by the setting of the feature structure 30 and can extend to the edge of the battery body 10 as much as possible, thereby reducing the dead zone area on the battery body 10 and increasing the effective power generation area of the solar cell, which helps to improve the conversion efficiency of the solar cell.

[0052] Optionally, as Figure 1 shown, along the second direction Y, the distance from the feature structure 30 to the edge of the adjacent battery body 10 is H1, satisfying: H1 ≤ 2000 μm.

[0053] In the embodiment of the present application, by setting a reasonable value range of the distance H1 from the feature structure 30 to the edge of the corresponding battery body 10, the blank area between the feature structure 30 and the edge of the battery body 10 is reduced, thereby reducing the dead zone area on the battery body 10 and helping to improve the conversion efficiency of the battery body 10.

[0054] It can be understood that when the distance H1 from the feature structure 30 to the edge of the corresponding battery body 10 is greater than 2000 μm, the distance between the feature structure 30 and the edge of the battery body 10 is relatively large, and a blank area will be formed between the feature structure 30 and the edge of the battery body 10. The carriers generated by the battery body 10 in this blank area cannot be effectively collected, resulting in a large dead zone in the battery body 10 and reducing the conversion efficiency of the battery body 10.

[0055] In a specific application, the end portions of the electrodes 20 on both sides of the feature structure 30 along the first direction X can be bent and extended into the above-mentioned blank area, so as to collect the carriers in the blank area by using the electrodes 20. However, although this setting reduces the dead zone area, the structure setting of the electrodes 20 is relatively complex, which not only increases the processing cost but also improves the process difficulty. In this application, by controlling the value range of the distance H1 from the feature structure 30 to the edge of the corresponding battery body 10, it is convenient for the structural layout and processing of the feature structure 30 and the electrodes 20 on the battery body 10, and at the same time, it can take into account reducing the dead zone area on the battery body 10 and improving the conversion efficiency of the battery body 10.

[0056] Specifically, the distance H1 can be set to any value such as 0μm, 10μm, 100μm, 300μm, 500μm, 800μm, 1000μm, 1200μm, 1500μm, 1700μm, 2000μm, etc. or the range between any two values.

[0057] Wherein, the distance H1 refers to the straight-line distance from the side of the feature structure 30 facing the edge of the battery body 10 along the second direction Y to the corresponding edge of the battery body 10.

[0058] Optionally, as Figure 1 shown, along the second direction Y, the distance from the feature structure 30 to the corresponding electrode 20 is H2, satisfying: H2 ≤ 3000μm.

[0059] In the embodiment of this application, by setting a reasonable value range of the distance H2 from the feature structure 30 to the corresponding electrode 20, it is avoided that the gap between the electrode 20 and the feature structure 30 is too large, resulting in a large dead zone on the battery body. In actual application, on the premise of ensuring that the feature structure 30 and the electrode 20 on the battery body 10 can be reasonably arranged, the distance between the feature structure 30 and the corresponding electrode 20 can be minimized as much as possible, so as to reduce the dead zone area on the battery body 10 and help improve the conversion efficiency of the battery body 10.

[0060] Specifically, the distance H2 can be set to any value such as 0μm, 10μm, 100μm, 300μm, 500μm, 800μm, 1000μm, 1200μm, 1500μm, 1700μm, 2000μm, 2500μm, 2800μm, 3000μm, etc. or the range between any two values.

[0061] It should be noted that, as Figure 1As shown, when the distance H2 is set to 0 μm, it means that the lower end of the feature structure 30 is flush with the upper edge of the corresponding second power generation region 12, and the upper end of the electrode 20 in the second power generation region 12 is flush with the upper edge of the second power generation region 12. Such a structure can also be achieved in practical applications, but it has higher requirements for the processing accuracy and alignment. Therefore, in practical applications, in order to facilitate processing, there is a certain distance between the end of the electrode 20 and the edge of the corresponding power generation region.

[0062] Among them, the distance H2 refers to the straight-line distance from the side of the feature structure 30 facing the corresponding electrode 20 along the second direction Y to the end of the electrode 20.

[0063] Optionally, as Figure 1 and Figure 2 shown, the surface of the battery body 10 is provided with a first power generation region 11 and a second power generation region 12 with opposite conductive types. The first power generation region 11 and the second power generation region 12 are alternately arranged at intervals along the first direction X. Electrodes 20 are provided in both the first power generation region 11 and the second power generation region 12; the width of the second power generation region 12 along the first direction X is greater than the width of the first power generation region 11 along the first direction X, and the feature structure 30 corresponds to at least one second power generation region 12 in the second direction Y.

[0064] In the embodiment of the present application, the surface of the battery body 10 is provided with alternately arranged first power generation regions 11 and second power generation regions 12, and the width of the second power generation region 12 is greater than the width of the first power generation region 11. Furthermore, the feature structure 30 is arranged to correspond to at least one second power generation region 12. Since the width of the second power generation region 12 is relatively wide, by making the feature structure 30 correspond to the relatively wide second power generation region 12, the setting requirements of the feature structure 30 can be met, thereby reducing the occupation of other regions by the feature structure 30, so that more regions on the battery body can be used for power generation.

[0065] In some examples, the surface of the battery body 10 is provided with a first power generation region 11 and a second power generation region 12 with opposite conductive types. Among them, semiconductor film layers are provided in both the first power generation region 11 and the second power generation region 12. Among them, the semiconductor film layer provided in the first power generation region 11 has the same doping type as the silicon substrate in the battery body, and the semiconductor film layer provided in the second power generation region 12 has a doping type opposite to that of the silicon substrate in the battery body. Furthermore, in order to improve the collection ability of minority carriers, the width of the second power generation region 12 is set to be greater than the width of the first power generation region 11. For example: when the silicon substrate of the battery body is N-type, the second power generation region 12 is provided with a P-type semiconductor film layer, that is, a P region, for collecting holes. For an N-type silicon substrate, the minority carriers are holes. At this time, the width ratio of the P region is set to be larger in order to improve the collection of minority carriers, thereby improving the battery efficiency.

[0066] It can be understood that if the feature structure 30 is made to correspond to the relatively narrow first power generation area 11, and the feature structure 30 itself needs to meet a certain width to be accurately recognized, in order to ensure the width of the feature structure 30, the feature structure 30 will also occupy the areas on both sides of the first power generation area 11 along the second direction Y. This will result in a relatively large gap between the first power generation area 11 corresponding to the feature structure 30 and the adjacent second power generation areas 12 on both sides. The relatively large gap will increase the dead zone area and reduce the effective power generation area, thereby affecting the power generation efficiency of solar energy.

[0067] Exemplarily, as Figure 16 shown, taking the silicon substrate in the battery body 10 as N-type as an example, the first power generation area 11 is the N area, and the second power generation area 12 is the P area. Diagram a shows that the feature structure 30 corresponds to the P area, that is, the feature structure 30 corresponds to the relatively wide second power generation area 12; diagram b shows that the feature structure 30 corresponds to the N area, that is, the feature structure 30 corresponds to the relatively narrow first power generation area 11. Comparing diagram a and diagram b, it can be seen that when the feature structure 30 corresponds to the relatively narrow first power generation area 11 (that is, the structure shown in diagram b), the gap between the first power generation area 11 corresponding to the feature structure 30 and the adjacent second power generation areas 12 on both sides is relatively large, increasing the dead zone area and reducing the effective power generation area of the battery. It should be noted that when other types of solar cells are used, it can be understood by reference, and details will not be elaborated here.

[0068] It can be understood that in the embodiments of the present application, the solar cell can be a back-contact battery. The electrodes 20 of the back-contact battery are all arranged on the back surface. An electron transport layer and a hole transport layer are arranged on the back surface of the battery to transport electrons and holes respectively, corresponding to the above-mentioned first power generation area 11 and second power generation area 12. During the processing of the electron transport layer and the hole transport layer on the back surface of the back-contact battery, patterning processing is required. During the patterning processing, accurate alignment can be performed based on the feature structure 30 on the battery body 10. Moreover, during the subsequent processing of the electrodes 20, identification and alignment can also be performed based on the feature structure 30.

[0069] In some embodiments, the back-contact battery includes but is not limited to: back-contact heterojunction solar cell (HBC cell), back-contact tunneling oxide passivated contact cell (TBC cell), composite passivated back-contact cell (HPBC cell), back-contact hybrid cell (HTBC cell), etc.

[0070] Exemplarily, the battery body 10 can be made of N-type crystalline silicon. On the back of the battery body 10, there are alternately arranged first power generation regions 11 and second power generation regions 12. An N-type semiconductor film layer, that is, an N region, is provided in the first power generation region 11; a P-type semiconductor film layer, that is, a P region, is provided in the second power generation region 12. An isolation region is provided between adjacent P regions and N regions to isolate the P region and the N region. Among them, in the first direction X, the width of the P region is greater than the width of the N region. Furthermore, at least one feature structure 30 can be provided at the edge of the battery body 10, so that the feature structure 30 corresponds to at least one P region. On the one hand, since the P region is relatively wide, it can ensure that the provided feature structure 30 has a certain width so that it can be accurately identified. On the other hand, compared with a narrower N region provided under the feature structure 30, providing a P region can increase the effective power generation area of the battery cell and improve the efficiency.

[0071] Optionally, the P-type semiconductor film layer can contain one or several elements in Group IIIA (for example, it can be boron). The N-type semiconductor film layer can contain one or several elements in Group VA (for example, it can be phosphorus). The materials of the N-type semiconductor film layer and the P-type semiconductor film layer can include any semiconductor material such as silicon, silicon-germanium, germanium, or gallium arsenide. In terms of the arrangement form of substances, the crystal phase of the semiconductor layer can be amorphous, microcrystalline, nanocrystalline, single crystal, or polycrystalline, etc. Among them, the materials of the N-type semiconductor film layer and the P-type semiconductor film layer can be the same or different. For example: The materials of the P-type semiconductor film layer and the N-type semiconductor film layer can both include doped polysilicon. Another example: The material of the P-type semiconductor film layer can include doped polysilicon, and the material of the N-type semiconductor film layer can include at least one of doped amorphous silicon, doped microcrystalline silicon, and doped nanocrystalline silicon. Another example: The material of the P-type semiconductor film layer can be doped single crystal silicon, that is, formed by diffusion on the surface of the P region of the silicon substrate, and the material of the N-type semiconductor film layer can be doped polysilicon. The P-type semiconductor film layer can be prepared by in-situ doping or non-in-situ doping. The N-type semiconductor film layer can also be prepared by in-situ doping or non-in-situ doping.

[0072] Optionally, as Figure 3 shown, when the feature structure 30 corresponds to a second power generation region 12, the width D0 of the feature structure 30 along the first direction X is less than or equal to the width D1 of the second power generation region 12 along the first direction X.

[0073] In an embodiment of the present application, a feature structure 30 is provided corresponding to a second power generation area 12, and the width D0 of the feature structure 30 is less than or equal to the width of the second power generation area 12. In this way, by arranging the feature structure 30 in the area corresponding to the edge part of the battery body 10 and opposite to a second power generation area 12, it can not only ensure that the feature structure 30 has a certain width and can be accurately recognized, but also avoid the feature structure 30 occupying other power generation areas, reducing the gap between the second power generation area 12 corresponding to the feature structure 30 and the first power generation areas 11 on both adjacent sides, thereby increasing the area of the battery body that can be used for power generation, reducing the dead zone area, and improving the power generation efficiency of the solar cell.

[0074] It can be understood that if the width D0 of the feature structure 30 is greater than the width of the second power generation area 12, the feature structure 30 will also occupy the areas on both sides of the second power generation area 12 along the second direction Y. This will result in a larger gap between the second power generation area 12 corresponding to the feature structure 30 and the first power generation areas 11 on both adjacent sides. The larger gap will increase the dead zone area and reduce the effective power generation area, thereby affecting the power generation efficiency of solar energy.

[0075] Optionally, as Figure 1 shown, when the feature structure 30 corresponds to a second power generation area 12, the electrode 20 in the second power generation area 12 corresponding to the feature structure 30 is a preset electrode. The preset electrode has a center line extending along the second direction Y, and the midpoint of the feature structure 30 is located on the extension line of the center line.

[0076] In an embodiment of the present application, by making the midpoint of the feature structure 30 located on the extension line of the center line of the corresponding preset electrode 20, it is convenient for the precise alignment between the feature structure 30 and the preset electrode 20. This is not only convenient for the layout design of the feature structure 30 and the electrode 20 on the battery body 10, but also convenient for the precise alignment of the electrode 20 based on the feature structure 30 during the battery processing.

[0077] In some embodiments, the feature structure 30 is an axisymmetric structure with the center line as the axis of symmetry. By setting the feature structure 30 as an axisymmetric structure, it is convenient for the rapid and accurate recognition of the feature structure 30 during the processing of the solar cell.

[0078] It should be noted that electrodes 20 are provided on both sides of the feature structure 30 along the first direction X. The distance from the feature structure 30 to the adjacent electrodes 20 on both sides can be set to be equal, or the distance from the feature structure 30 to the adjacent electrodes 20 on both sides can be made unequal, which can be flexibly set according to actual needs and is not limited herein.

[0079] Optionally, a semiconductor film layer is further provided on the surface of the battery body 10, and the electrode 20 is disposed on the side of the semiconductor film layer away from the battery body 10; when the feature structure 30 corresponds to a second power generation area 12, the doping type of the semiconductor film layer on the second power generation area 12 is the same as the doping type of the semiconductor film layer on the feature structure 30.

[0080] Specifically, semiconductor film layers are respectively provided on the surface of the battery body 10 at positions corresponding to the first conductive area and the second conductive area, and the doping type of the semiconductor film layer in the first conductive area is opposite to the doping type of the semiconductor film layer in the second conductive area. Correspondingly, a semiconductor film layer is also provided on the surface of the battery body 10 in the area where the feature structure 30 is provided. When the feature structure 30 corresponds to a second power generation area 12, the doping type of the semiconductor film layer provided on the feature structure 30 is the same as the doping type of the semiconductor film layer on the second power generation area 12.

[0081] It can be understood that the feature structure 30 corresponds to a second power generation area 12, and a semiconductor film layer is provided in the second power generation area 12, and the electrode 20 is provided on the surface of the semiconductor film layer. If, when preparing the electrode 20, due to factors such as printing errors, the length of the electrode 20 exceeds that of the corresponding second power generation area 12, the end of the electrode 20 may extend to the feature structure 30 at this time. At this time, if the doping type of the semiconductor film layer on the feature structure 30 is opposite to the doping type of the semiconductor film layer on the corresponding second power generation area 12, the same electrode 20 will be connected to two semiconductor film layers with different doping types, which will cause a short circuit. Therefore, in the embodiment of the present application, by setting the doping type of the semiconductor film layer on the second power generation area 12 to be the same as the doping type of the semiconductor film layer on the feature structure 30, the risk of short circuit of the electrode 20 in the second power generation area 12 can be effectively avoided, which can not only improve the safety of the solar cell, but also reduce the processing precision requirements for the electrode 20 in the second conductive area, facilitating actual production and processing.

[0082] Optionally, as Figure 6 shown, when the feature structure 30 corresponds to a second power generation area 12 and a first power generation area 11, the width of the feature structure 30 in the first direction X is D0, the width of the second power generation area 12 in the first direction X is D1, the width of the first power generation area 11 in the first direction X is D2, and the distance between the adjacent first power generation area 11 and the second power generation area 12 is D3, satisfying: D0≤D1+D2+D3.

[0083] In the embodiment of the present application, by setting the feature structure 30 to correspond to a second power generation area 12 and a first power generation area 11, the width of the feature structure 30 along the first direction X can be increased, thereby reducing the recognition difficulty of the feature structure 30 and facilitating the rapid and accurate recognition of the feature structure 30 during the battery processing. At the same time, by setting D0≤D1+D2+D3, the feature structure 30 is restricted within the area corresponding to two adjacent power generation areas, so as to avoid the feature structure 30 occupying too much space, so that more areas on the battery body 10 can be used for power generation, thereby improving the power generation efficiency of the battery body 10.

[0084] Optionally, as Figure 2 shown, the electrode 20 corresponding to the feature structure 30 along the second direction Y is the first target electrode 21, and the electrodes 20 other than the first target electrode 21 among the plurality of electrodes 20 are the second target electrodes 22. The length of the first target electrode 21 along the second direction Y is less than the length of the second target electrode 22 along the second direction Y.

[0085] In the embodiment of the present application, by setting the length of the first target electrode 21 along the second direction Y to be less than the length of the second target electrode 22 along the second direction Y, that is, by shortening the length of the first target electrode 21, a certain electrode blank area is reserved between the end of the first target electrode 21 and the first edge 10a of the battery body 10 for setting the feature structure 30. In this way, it is not only convenient for the setting and processing of the feature structure 30 on the battery body 10, but also can avoid the recognition interference of the second target electrode 22 on the feature structure 30.

[0086] It should be noted that the first target electrode 21 corresponding to the feature structure 30 along the second direction Y can be one or more than two, and can be flexibly set according to actual needs, and is not limited here. Exemplarily, as Figures 3 to 5 shown, the feature structure 30 can correspond to the electrode 20 in one power generation area; as Figure 6 shown, the feature structure 30 can correspond to the electrodes 20 in two power generation areas; as Figure 7 shown, the feature structure 30 can also correspond to the electrodes 20 in three power generation areas.

[0087] Optionally, as Figure 2 shown, the second target electrode 22 includes a first sub-electrode 221 and a second sub-electrode 222 other than the first sub-electrode 221; the edge of the battery body 10 corresponding to the feature structure 30 is the first edge 10a. Along the second direction Y, the distance H3 between the first sub-electrode 221 and the first edge 10a is greater than the distance H4 between the second sub-electrode 222 and the first edge 10a, and the first sub-electrode 221 is close to the feature structure 30.

[0088] It can be understood that feature structures 30 can be provided at both edge positions of the battery body 10 along the second direction Y, so as to meet different alignment requirements by identifying the feature structures 30 at different positions during the battery processing. Among the multiple feature structures 30, at least one target feature structure can be included, such that at least one first sub-electrode 221 is provided in the second target electrode 22 corresponding to the target feature structure, and the distance between the first sub-electrode 221 and the first edge 10a is greater than the distances between other second target electrodes 22 and the first edge 10a. In this way, during the identification and positioning, the position of the target feature structure can be determined based on the identification of the first sub-electrode 221, and then the up-and-down position of the battery body 10 in the second direction Y can be determined by identifying the target feature structure, thereby facilitating the actual battery processing.

[0089] Correspondingly, the second target electrodes 22 corresponding to the other feature structures 30 can be set to the same length and no length difference processing is required, so as to facilitate the actual processing and improve the collection ability of the electrode 20 at the same time.

[0090] Optionally, as Figure 2 shown, the edge of the battery body 10 corresponding to the feature structure 30 is the first edge 10a, and along the second direction Y, the distance H1 between the feature structure 30 and the first edge 10a is less than or equal to the distance H4 between the second target electrode 22 and the first edge 10a.

[0091] In the embodiment of the present application, by setting the distance between the feature structure 30 and the first edge 10a to be less than or equal to the distance between the second target electrode 22 and the first edge 10a, that is, setting the feature structure 30 closer to the edge of the battery body 10, in this way, the space at the edge of the battery sheet can be fully utilized to provide the feature structure 30, thereby improving the compactness of the surface structure layout of the battery body 10.

[0092] Certainly, the distance between the feature structure 30 and the first edge 10a can also be set to be greater than the distance between the second target electrode 22 and the first edge 10a to meet different layout requirements, and those skilled in the art can flexibly set according to actual needs and are not limited herein.

[0093] In some embodiments, as Figures 8 - 15 shown, taking the heterojunction back contact battery as an example, the present application provides a method for manufacturing a solar cell, and the specific process is as follows:

[0094] Step 1, as Figure 8As shown, a first passivation layer 200 (such as a SiOx layer), a first conductive layer 300 (such as an n-poly layer), and a mask layer 400 are sequentially deposited on the back surface B of the silicon substrate 100 by using an LPCVD device. Among them, the thickness range of the first passivation layer 200 is 0.5 nm - 5 nm, the thickness range of the first conductive layer 300 is 30 nm - 300 nm, the thickness range of the mask layer 400 is 10 nm - 1000 nm, and the material of the mask layer 400 can be selected from SiNx or SiOx, etc.

[0095] Step 2, as Figure 9 shown, laser etching is used to open the mask layer 400 to form a first opening area M1, and laser etching is used to etch a feature structure 30 on the silicon substrate 100. Among them, the width of the first opening area M1 is set to 20 μm - 2000 μm. It can be understood that the first opening area M1 corresponds to the second power generation area 12 described above.

[0096] Step 3, as Figure 10 shown, wet etching is used to remove the first passivation layer 200 and the first conductive layer 300 in the first opening area M1, and the surface of the silicon substrate 100 at the corresponding position of the first opening area M1 is textured. Of course, other methods can also be used to remove the first passivation layer 200 and the first conductive layer 300 in the first opening area M1, which is not limited here.

[0097] Step 4, as Figure 11 shown, a second passivation layer 500 and a second conductive layer 600 are deposited on the back surface B of the silicon substrate 100, and a third passivation layer 700 and an antireflection layer 800 are deposited on the front surface F of the silicon substrate 100. Among them, both the second passivation layer 500 and the third passivation layer 700 can be an intrinsic amorphous silicon layer; or, the second passivation layer 500 is intrinsic amorphous silicon, and the third passivation layer 700 is an AlOx layer. The thickness range of the second passivation layer 500 and the third passivation layer 700 is 3 nm - 20 nm. The second conductive layer 600 can be a P-type amorphous silicon layer, and the thickness range of the second conductive layer 600 is 3 nm - 100 nm. The antireflection layer 800 can be a SiNx layer, and the thickness range of the antireflection layer 800 is 10 nm - 300 nm.

[0098] Step 5, as Figure 12As shown in the figure, a laser is used to open the second passivation layer 500 and the second conductive layer 600 to form a second opening area M2. The width of the second opening area M2 is 10um - 1000m. The second opening area M2 corresponds to the first power generation area 11 mentioned above. In this step, it is necessary to ensure a certain parallel spacing between the second opening area M2 and the first opening area M1. Therefore, during the processing, it is necessary to identify the position of the first opening area M1, and the position can be judged by identifying the feature structure 30 processed in step 2, so as to accurately process the second opening area M2.

[0099] Step 6, as Figure 13 shown, a transparent conductive layer 900 (such as a TCO thin film layer) is deposited on the back surface B of the silicon substrate 100 by using a PVD device or an RPD device. The thickness range of the transparent conductive layer 900 is 20nm - 200nm.

[0100] Step 7, as Figure 14 shown, an etching paste is used to etch the transparent conductive layer 900 between the first power generation area 11 and the second power generation area 12 to form a third opening M3. The width range of the third opening M3 is 20μm - 200μm.

[0101] Step 8, as Figure 15 shown, electrodes 20 are respectively prepared in the first power generation area 11 and the second power generation area 12 by means of screen printing, etc. During the preparation of the electrodes 20, accurate alignment is carried out by identifying the feature structure 30 on the silicon substrate 100, so as to prepare a solar cell.

[0102] It should be noted that the above is only an explanatory description taking the preparation process of the hybrid back contact battery as an example. The battery in this application is not limited to the hybrid back contact battery, and the preparation processes of other types of batteries can be referred to and will not be elaborated here.

[0103] Optionally, an embodiment of the present application further provides a photovoltaic module, including a plurality of battery strings. The battery strings include a plurality of solar cells and a plurality of interconnecting members. The interconnecting members are used to connect the plurality of solar cells in series; wherein, the solar cells include the solar cells in the above embodiments.

[0104] In the embodiments of the present application, the photovoltaic module includes a solar cell. By arranging a feature structure 30 at a position close to the edge on the battery body 10, it is convenient for identification and positioning during the battery processing. At the same time, by setting the position of the feature structure 30 on the battery body 10, the feature structure 30 corresponds to at least one electrode 20 along the second direction Y, and the orthographic projection of the feature structure 30 along the first direction X overlaps with the orthographic projection of at least part of the electrode 20. In this way, by defining the positional relationship between the feature structure 30 and the electrode 20 on the battery body 10, it is not only convenient for the design and processing of the feature structure 30 on the battery body 10, but also can reduce the dead zone area in the battery body, thereby increasing the area of the battery body available for power generation and improving the conversion efficiency of the solar cell.

[0105] In the description of this specification, the description with reference to terms such as "one embodiment", "some embodiments", "schematic embodiments", "examples", "specific examples", or "some examples" means that the specific features, structures, materials, or characteristics described in connection with the embodiment or example are included in at least one embodiment or example of the present application. In this specification, the schematic representations of the above terms do not necessarily refer to the same embodiment or example. Moreover, the specific features, structures, materials, or characteristics described can be combined in a suitable manner in any one or more embodiments or examples.

[0106] Although the embodiments of the present application have been shown and described, those of ordinary skill in the art can understand that various changes, modifications, substitutions, and variations can be made to these embodiments without departing from the principles and spirit of the present application. The scope of the present application is defined by the claims and their equivalents.

Claims

1. A solar cell, characterized in that: include: A battery body (10), wherein a plurality of electrodes (20) are arranged on a surface of the battery body (10), the surface having a first direction (X) and a second direction (Y) intersecting each other, and the plurality of electrodes (20) are arranged at intervals along the first direction (X); the battery body (10) is provided with a characteristic structure (30) on a side edge close to the second direction (Y), and the characteristic structure (30) is used for identification and positioning; wherein the characteristic structure (30) corresponds to at least one of the electrodes (20), and the orthographic projection of the characteristic structure (30) along the first direction (X) overlaps with the orthographic projection of at least part of the electrode (20).

2. The solar cell according to claim 1, characterized in that Along the second direction (Y), the distance from the characteristic structure (30) to the adjacent edge of the battery body (10) is H1, satisfying: H1≤2000 μm.

3. The solar cell according to claim 1, characterized in that Along the second direction (Y), the distance between the characteristic structure (30) and the corresponding electrode (20) is H2, satisfying: H2≤3000 μm.

4. The solar cell according to claim 1, characterized in that The surface of the battery body (10) is provided with a first power generation area (11) and a second power generation area (12) of opposite conductivity types, the first power generation area (11) and the second power generation area (12) are arranged alternately and spaced along the first direction (X), and the first power generation area (11) and the second power generation area (12) are both provided with the electrode (20); the width of the second power generation area (12) along the first direction (X) is greater than the width of the first power generation area (11) along the first direction (X), and in the second direction (Y), the characteristic structure (30) corresponds to at least one of the second power generation areas (12).

5. The solar cell according to claim 4, characterized in that: When the characteristic structure (30) corresponds to one of the second power generation regions (12), the width of the characteristic structure (30) along the first direction (X) is less than or equal to the width of the second power generation region (12) along the first direction (X).

6. The solar cell according to claim 4, characterized in that: In the case where the characteristic structure (30) corresponds to one of the second power generation areas (12), the electrode (20) in the second power generation area (12) corresponding to the characteristic structure (30) is a preset electrode, and the preset electrode (20) has a center line extending along the second direction (Y), and the midpoint of the characteristic structure (30) is located on the extension line of the center line.

7. The solar cell according to claim 4, characterized in that: A semiconductor film layer is also provided on the surface of the battery body (10), and the electrode (20) is provided on a side of the semiconductor film layer that is away from the battery body (10); when the characteristic structure (30) corresponds to one of the second power generation areas (12), the doping type of the semiconductor film layer on the second power generation area is the same as the doping type of the semiconductor film layer on the characteristic structure.

8. The solar cell according to claim 4, characterized in that: In the case where the characteristic structure (30) corresponds to one of the second power generation areas (12) and one of the first power generation areas (11), the width of the characteristic structure (30) along the first direction (X) is D0, the width of the second power generation area (12) along the first direction (X) is D1, the width of the first power generation area (11) along the first direction (X) is D2, and the spacing between adjacent first power generation areas (11) and second power generation areas (12) is D3, satisfying: D0≤D1+D2+D3.

9. The solar cell according to any one of claims 1 to 8, characterized in that: The electrode (20) corresponding to the characteristic structure (30) along the second direction (Y) is a first target electrode (21), and the electrodes other than the first target electrode (21) among the multiple electrodes (20) are second target electrodes (22), and the length of the first target electrode (21) along the second direction (Y) is smaller than the length of the second target electrode (22) along the second direction (Y).

10. The solar cell according to claim 9, characterized in that: The second target electrode (22) includes a first sub-electrode (221) and a second sub-electrode (222) other than the first sub-electrode (221); the edge on the battery body (10) corresponding to the characteristic structure (30) is the first edge (10a); along the second direction (Y), the distance (H3) between the first sub-electrode (221) and the first edge (10a) is greater than the distance (H4) between the second sub-electrode (222) and the first edge (10a), and the first sub-electrode (221) is close to the characteristic structure (30).

11. The solar cell according to claim 9, characterized in that: The edge of the battery body (10) corresponding to the characteristic structure (30) is a first edge (10a), and along the second direction (Y), the distance between the characteristic structure (30) and the first edge (10a) is less than or equal to the distance between the second target electrode (22) and the first edge (10a).

12. The solar cell according to claim 1, characterized in that The orthographic projection of the characteristic structure (30) on the surface is in the shape of a circle, an ellipse, a polygon, a cross, or a ring, or a combination of two or more thereof.

13. A photovoltaic module, characterized in that: It comprises a plurality of battery strings, wherein the battery strings comprise a plurality of solar cells and a plurality of interconnectors, wherein the interconnectors are used to connect the plurality of solar cells in series; wherein the solar cells are the solar cells according to any one of claims 1 to 12.

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